Australia [Status and technology of polymer-containing fibrous materials in the Eastern Hemisphere]

Enough commercial irradiators with particle accelerators or cobalt-60 sources have been built in recent years to give confidence that the technology for treating material with gamma or electron radiation is practical and well established. Experience has shown that irradiation of packaged materials, with gamma radiation, involves a complex arrangement of conveyors to ensure efficient utilization of the radiation, particularly when the treatment requires a dose in the megarad range. It is therefore impractical to consider that small-scale irradiators might favourably compete on economic grounds with conventional methods to achieve similar results. It is the capital cost, apart from intangible considerations, which places any proposed radiation process at a disadvantage with respect to alternative methods even though operating costs and material costs may be low. Furthermore, high capital cost demands a high utilization rate and an assured long-term market for the product to minimize the radiation cost per unit. It is intended in this contribution to the study group to survey briefly the possibilities for an irradiated wood-polymer process in terms of the existing technology in Australia